Circuits for rotary selector and connector switches



SELECTOR |02 April 23, 1957 P. BAKKER 2,790,031

CIRCUITS NCR ROTARY SELECTOR AND CONNECTOR SWITCHES Filed may 4, 195s 4 sheets-sheet I I I PIER BAKKER f g 74m April 23, 1957 Ff. BAKKER 2,790,031

CIRCUITS ECR ROTARY SELECTOR AND CONNECTOR swITCREs r Filed lay 4, 195i 4 Sheets-Sheet 2 R.B.TONE T CONNECTOR soo TPL- 64 son en illl -FT25' l l l. i a 245\ I I 22 i 2443 l l P. BAKKER L CIRCUITS FOR lROTARY SELECTOR AND CONNECTOR SWITCHES Filed lay 4. 1953 April 23, 1957 4 Sheets-Sheet 3 CONNECTOR 30 0 o unuvocoo. ewoooooos o so .new 0% .o Q.. n m n I1" H2 w n a 3 Il 3 3 M :l 3 w l I s u/flr. M ou.. e l 0000 l o .lo |0000 o. aan. I. l. .IK 2\ 3 3 M n fl .m w. a m M\ M 3 3 3 3 n INVENTOR. PIER aumen v "Y www ATTY.

April 23, 1957- P. BAKKER C 2,790,031

CIRCUITS FOR ROTARY SELECTOR AND CONNECTOR SWITCHES v Filed lay 4, 1953 4 Sheets-Sheet 4 FIG-4 u nlm. svn H BANK AuxluAm svmcn um c m INVENToR. PlER BAKKER Y ATTY.

Unid StatesPau-1ct f CIRCUITS FOR ROTARY SELECTOR `r CONNECTOR SWITCHES PierBakker, Chicago, Ill., assignor to General Telephone Laboratories, Incorporated, a corporation of Delaware Application May 4, 1953, Serial No. 352,899

16 Claims. (Cl. 179-18) This invention relates to telephone systems and more particularly to a telephone system using single-motion rotary switches for extending connections therein.

2,790,031 Patented Apr. 2v3, 1957 ice Figs. 2 and 3 show a connector accessible to said selec- I' tor and an auxiliary switch associated withthe connector;

Fig. 4y illustrates the arrangement of outlet groupsior.v

either selector 102 or connector 300 and connections to the auxiliary switch associated therewith. r-

Referring to Fig. 4 more specifically, it Willbe' seen that the numerical switch, either selector 102 or connector 300, is a 16 level, 25 point (plus a normal position) rotary switch having l groups of outlets, 10 outlets per group. Outlet groups 11--10, 21-20, 31-30, 71-70 and 81-80, which groups are selected Iin response to,

` digits 1, 2, 3, 7 and 8 respectively, are connected to the It is old in the art to utilize either an auxiliary switch or marking relays to control group skipping in slnglemotiony numerical switches to control the selection ofl a group of lines or trunks Where more than one group appear in the same level; and, in applicants co-pending application Serial No. 119,082, led October l, 1949,

now Patent No. 2,646,466, issued July 21, 1953, an auxiliary switch together with marking relays was utilized-to control this group skipping.

However, in said co-pending application, the numerical r,

switch does not begin stepping to accomplish its group skipping operation until after the auxiliary switch hasV been set to mark a desired group; while inthe present application the auxiliary and numerical switches operate simultaneously. y

Further, no prior system in which outlet group selection is initiated `during the receipt of impulses shows an interlock between the group marking means and the circuit means marked for controlling group skipping for the4 purpose of providing additional time to a numerical switch to permit the group skipping operation to catch up t0 the dialled impulses in order to minimize the danger of establishing wrong connections, i. e. each marking relay operates in response to a certain impulse, becomes effective when the wipers reach the group which it marks-and .l

restores when the wipers reach the end of said marked group. While the wipers are being stepped to a desired1 group, the auxiliary switch is selecting-in responseto received impulses, a desired wiper set by way of the' As a result, a different .outlet v auxiliary switch wipers.

group in the numerical switch may be selected in response to some of said impulses merely by selecting different numerical switch wiper sets without moving the numerical switch wipers, thereby permitting absorption of. impulses. v

It is an object of this invention to provide singlemotion numerical switches with an-interlock circuit so as to minimize the problem of -the critical adjustment. ofA

switch huntingspeed to substation dial speed. l.

A feature of this invention is the newand novel linterlock circuit including an auxiliaryrswitch together with marking relays anda control bank in the numerical switch.

A further feature is the use ofthe above mentioned auxiliary switch for selecting the desired numerical switch i wipers.

A further feature is the simultaneous steppingof the auxiliary and numerical switches to complete group selection while the group selecting digit is being received.

Further features will be evident upon a persual lofthe following disclosure in which: v

Fig. 1 shows a substation and the line associated therewith, a 4selector andan auxiliary switch associated therewith and, in block diagram `form, a line circuit, a finder,

and a finder allotter;

iirst halves of the bank levels; and the outlet groups 417-40, 51-50, 61-60, 91-90 and '0l-00, Which` groups are selected in response to digits 4,15,-6,'19,;i0

respectively, are connected to the last halves of the bank levels.

However, the wipers having access to outlets 71-00 are displaced 180 from the wipershaving access and ninth contacts to thev wipers having access to, lout-l lets 71-70 and 91--90; and the eighth andtenth. conv tacts to the wipers having access to the outlets 8,1-80 and 01-00. The auxiliary switch wipers select the proper t. numerical switch wipers `and extend connections thereto. Bank connections of the control levels--in Fig. 4, the

lower auxiliary switch level and the lower right numerical switch level EC-are shown in Figs. 1, 2 and 3, the bottom levels being the control levels.

Figs. 1 and 3 each show only one.set of levels for the sake of clarity and ease of explanation.

Group selection in selector 102 is accomplished under:y l

the control of the auxiliary switch and two marking relays u In response to a fourth impulse in a series ot impulses received by selector 102, relay R is operated by way of auxiliary switch wiper 192 and its f fourth contact to complete a circuit for operating the selector motor magnet M185 to advance -the .selector Il wipers a quarter of a revolution, the wipers having access to outlet groups 41-40, 51-50, and 61-60 stopping on the rst positions in said groups. f

Similarly, in response to a seventh impulse, relay R i is operated by way of wiper 192 and its seventh `contact to operate M to advance the selector wipers another. quarter of a revolution, the wipers having access tof: A

outlet groups 71-70 and 81-80 stopping on thc lirstA positions in said groups.

In response to a ninth impulse, operated by way of wiper 192 and its ninth contact to operate M185 to advance the selector wiper anotherv 1 quarter of a revolution, the wipers having access to outlet groups 91-90 and 01-00 stopping on the lirst positions in said groups.

Group selection in connector 300 is accomplished in ay similar manner.

An interlock arrangement is provided in each numericalfswitch whereby each marking relay, which controls stepping to `accomplish group skipping, is operated in response to a predetermined impulse received and is held operated until the group skipping operation, which it" controls is completed; as a result, impulses received subsequent to the operation of the marking relay but prior to completion of the group skipping operation ,Byl means of the same interlock arrangement, if a m kingY not interfere with the group skipping operation:

relay is operatedy while the wipers ofthe numerical switch are still being stepped across one set of groups,

relay R165 iS said relay will be held operated-and ineffective until the wipers reach the first position in the group with which said relay is associated, at which time the relay becomes effective to cause the numerical switch magnet to step the wipers over said last-mentioned group.

Several line circuit, nder and allotter arrangements well-known in the art, such as that shown in the Saunders Patent No. 1,849,694, may be used in conjunction with the selector and connector disclosed in detail herein. The allotter is one which makes a test for battery on the selector private conductore. g. 134-before taking into use the finder associated with said selector. Such a test is often utilized to check for faulty battery fuses,

An arrangement employing a single'wiper rather than a double wiper in each level of the numerical switches together with a staggered arrangement of the wipers has been shown since wiper friction becomes an important factor in the design of switches having a great number of levels' and wipers.

Seizure of the selector When a call is`initiated, for example at substation 100 arid anderand finder allotter, for example 101, extend the line associated with substation 100 to selector 102 in a manner well-'known'in the art, the line relay R120 is operated overa circuit extending from ground at contacts 161, over contacts 141,` the lower winding of R120, contacts 113, over the extended line to substation 100 and bac'klthrough contacts 111 to the upper winding of R120. At contacts`121, R120`comp1etes an obvious circuit for operating hold relay" R125.

*At'contacts 126 and'127, R125 removes battery from the`private"con'ductor` 134 and places ground potential thereon' to busy mark the selector; at contacts 128, completes 'a self-interruptingcircuit, including wipery 182and contacts' 186, forv operating the selector motor magnet M185 to advance the selector wipers one step; at contacts 129, completes a circuit including olf-normal contacts 107, relayR135, contacts191 and the winding of the auxiliary switch motor magnet M190 of the auxiliary switch for'operating changeover relay R135 over its high resistance upperwinding (M190 will not operate); and, at contacts'i132', prepares a pulsing circuit for M190.

At'contacts 136, R135 completes an obvious circuit for operating relay R145; at contacts 137 and 138, furtherprepares theL pulsing'circuit for M190; at contacts 139,rreturn's dial ton'e toV substation 100 over the previously jdescribed operating circuit of R120; and,y at contacts 142, places ground potential upon the wiper 192.

At contacts 147, R145 short circuits the upper winding of R155`to give it slow to release characteristics; and, at

contacts 148,' opens the operating circuit for switching relay R110. p

The selector is now ready to receive the first digit, relays R120, R125, R135 and R145 being in operated positions.

Operaln of the wiper selecting and group skipping 'equipment For purposes of this description, it will be noted that a three digitv subscriber number will be used and that calls will be assumedvto be extended over only one selector and the connector.

pulses over the previously described pulsing circuit as a result of its tendency to restore slowly when connected in parallelwith the' very low resistance winding of M190.V

In response tothe operations of M190, the wipers 152,

153 and 154 are moved thereby to select the proper set of selector wipers.

In response to the third, sixth and eighth impulses of a digit having, for example, nine impulses, a circuit including contacts 142, wiper 192 and the third, sixth and eighth contacts accessible to wiper 192 will be completed for operating busy relay R155 over its lower winding. Contacts 151 have been opened by R145 however so that busy tone is not returned to substation 100.

In response to the fourth impulse, a circuit including contacts 142, wiper 192, the fourth bank contact accessible thereto, and the operated contacts 157 is completed for operating marking relayvR over its upper winding. Said relay operates contacts 166 to lock itself operated, operates contacts 167 to prepare a circuit for restoring itself, and operates contacts 171 to complete an obvious self-interrupting circuit including the first l0 contacts accessible to control wiper 182 for operating M185 to step al1 of the wipers ten steps to bring the selector wipers having access to outlets 11-60 to the eleventh bank position. Then the lower winding of R165 will be energized in series with M185 over a circuit including contacts 167, the eleventh contact accessible to wiper 182 and wiper 182. M185 does not energize in series with R165. The upper and lower windings of R165 are differentially wound and R165 will therefore restore rapidly when both windings are energized. After R165 restores, M185 will'be operated over a circuit includingicontacts 128, 147, 168, said eleventh contact and wiper 182 to step said wipers to the twelfth position whereupon wiper 182 is grounded to again operate M185 to step said wipers to the thirteenth position which is the rst position of the 41-60 outlet groups.

In a similar manner, R175 will be operated in response to the seventh impulse to cause M to step the selector wipers to the twentythird bank position at which time R175 will be restored and M185 will operate to step all the wipers four steps to bring the Wipers having access to outlets 71-00, which wipers include wipers 162, 163

and 164, to'the rst bank position. It will be noted that the operation of R175 does not affect the rst group skipping operation. It merely extends ground from contacts 181 to the second group of multipled contacts accessible to wiper 182. Then, when wiper 182 encounters the lrst of said second group of contacts, the second group skipping operation will start.

In a manner similar to that previously described, R165 will be reoperated in response to the ninth impulse to again cause M185 to step all the wipers to bring the wipers having access to outlets 71-00 to the eleventh bank position whereupon relay R165 will restore and M185 will step all the wipers to bring the Wipers having access to outlets 71-00 to the thirteenth bank position to select outlets 91-00. It will be noted that even if the second group skipping operation is not completed when R165 reoperates, said relay will lock itself operated` and extend ground potential from contacts 171 to the trst group of multipled bank contacts accessible to wiper 182.v Then, when Wiper 182 encounters the rst bank contact accessible thereto, the third group skipping operation will begin.

The selector wipers 162, 163 and 164 have now been selected by wipers 152, 153 and 154, in response to said nine impulses, and wipers 1,62, 163 and 164 have been stepped to the contacts marked 91.

Selection of an idle connector vpletedfand R165 restored; R145 restoring closes contactsv 148'aiid 146to lcomplete a circuit including switching arsenal switching relay R110 will be operated over a circuit extending from ground over contacts 127 and 156, through the winding of R110, over contacts 131, 148, 109 and 186 through the winding of M185 to battery. (M185 will not operate.)

Assume that the selector wipers stop on contacts terminating in idle connector 300. When R110 operates,

it closes contacts 112 and 114 to extend the line associated with substation 100 over wipers 152 and 153, wipers 162 and 163, conductors 201 and 202, and contacts 211 and 213 to the windings of line relay R220 to operate R220; at contacts 117, R110 completes a circuit for holding itself operated after R125 restores contacts 131 to open the original operating circuit of R110; and at contacts 111 and 113, R110 opens the operating circuit of R120 to restore R120. R125 restores in response to the restoration of R120 to open contacts 127; however, hold relay R230 of the connector will have operated contacts 231 in response to the operation of R220 thereby to return ground over conductor 200, wipers 164 and 154, and contacts 146 and 116 to private conductor 134.

If all trunks in the 91-90 group had been busy the selector wipers would have been stepped to the contacts following those marked 90, at which time a circuit including contacts 128, the upper winding of busy relay R155, contacts 178 and 183, wiper 182, contacts 186 and M185 would be completed for operating R155. R155 operates contacts 159 to extend busy tone from contacts 151, over contacts 141 and 113 to the calling line.

Operation of the connector As previously described, line relay R220 is operated and followed by the operation of hold relay R230 when connector 300 is seized. R230 operates contacts 231 to ground the private conductor 200, contacts 232 to prepare a pulsing circuit for the auxiliary switch magnet M340, and contacts 234 to complete a circuit over the upper winding of changeover relay R280, conductor 318, off-normal contacts 347 and magnet M340 for operating R280. At contacts 282, R280 grounds control wiper 364 of the auxiliary switch over conductor 308; and at contacts 283 to 285 further prepares the pulsing circuit for M340.

In response to each impulse in a second series 'of impulses received, R220 will restore land reoperate to momentarily extend ground from contacts 222, over contacts 232, 283 and 285 and conductor 309 to M340 to oper- :ate said. magnet. R280 will remain operated lover its lower winding during Isaid series lof impulses `due to its slow-to-.release characteristic while its lower winding is in parallel with the winding of M340. Wipers 361, 362 and 363 will perform the wiper selection function in a manner similar to that described with respect to wipers 152, 153 and 154. In response to sai-dseries of impulses, the connector motor magnet M350, under the control of its :auxiliary switch, intermediate relay R310 and marking relay-s R320 and R330 will cause the connector wipers to be stepped to .a position before a predetermined group of lines all in .a manner similar to that in which M185 caused :the selector wipers ito be stepped to a predetermined group of trunks under the control of its auxiliary switch :and marking relays.

Upon the termination of said series of impulses, changeover relay R280 restores thereby to prepare a point at 6 v contacts 284 in the pulsing circuit to the connector magnet M350.

In response to the first impulse in a third series of impulses received, R270 will operate over a circuit including its lower winding, contacts 222, 232, 284 and 263 and will close contacts 275 to complete .a pulsing circuit for the connector motor magnet M350. At contacts 273,n R270 will short circuit its upper winding to cause it to be slow-torelease and thereby to remain operated during; said third series of impulses; at contacts 271, prepares a circuit `for `operating busy relay R260; and, at contacts# 274, .completes an alternate path for said pulsing circuiti in case :busy relay R260 should operate contacts 263 as the connector wipers are stepped over lines (which may' be busy) to said predetermined line.

In response to each impulse in said third series of impulses received, P220 will restore and reoperate to operate M350 over a pulsing circuit including contacts 222, 232, 284, 263, 275 and 257, :and conductor 317. M350 steps the connector wipers to a predetermined line in said predetermined group of lines.

R27 0 will begin to release slowly upon the termination of said third series of impulses. Assume that said predetermined line is one accessible to wipers 397, 398 and 399 and that said Wipers are connected to wipers 361,

362 .an-d 363 respectively. If said predetermined line is p busy, wiper 399 will encounter ground ythereby to complete a circuit over wiper 363, and contacts 331 and 321, conductor 366, and contacts 281, 272 and 256 tto busy relay R260 to operate said relay. At contacts 264, R260 will extend a busy tone over contacts 243 and 211 to the calling line, which line has been extended lto conductors 281 and 202 .as previously described; at contacts 262, prepares a circuit for maintaining itself operated after R270 restores Ito lopen contacts 272, said circuit being completed when contacts 276 close and contacts 272 `open; and, at contacts 263, opens the original operating circuit of R270, thereby to prevent a reoperation of R270 when line relay R220 restores upon abandonment yof .the call.

1f said predetermined line i's idle, wiper 399 will en` counter resistance battery trom the cut-off relay of the. line circuit associated with said predetermined line; and, when R270 restores, the switching relay R250 will operate in series with said cut-oir` relay over a circuit inclucling contacts 231, conductor 304, contacts 311, con ductor 305, contacts 261, the upper winding of R250,,

contacts 271 and 281, conductor 30o, contacts 321 and 331'; and wipers 363 and 399 all in a manner'well known im the art.

At contacts 299, R250 returns a ring back tone over contacts 243 and 211 to the calling line (which has been extended to conductors 201 and 262) to notify the calling party that the called line is being rung; at contacts 251 and 252, completes a circuit including the upper winding of ring-cuto1t relay R240, contacts 241 and 245, con ductors 301 and 302, wipers 361 and 362, and wipers 397 and 3% for extending ringing current to the predetermined line, all in a manner well known in the art; at contacts 254 and 253, short-circuits its upper Winding to make itself slow-to-release and grounds conductor 303 to insure the operation of the cut-01T relay associated with the called line and to busy mark said predetermined called line; at contacts 255, completes an obvious circuit for maintaining itself operated over its lower winding; and, at contacts 258, completes a circuit for starting the ringing machine generator (not shown) usually common to all equipment in an exchange, if the generator not already in operation.

Ring-cut-off relay R240 is slow-to-operate and, as is well known in the art, will not operate until the called party answers to complete a path for direct current through its upper winding.

R240, operating when the call is answered, closes contacts 242 and 244 to complete the talking circuit and a circuit of operating back bridge relay R210 all in a man1 ner well known in the art; closes contacts 246 to complete an obvious circuit for maintaining itself operated; at contacts-247, opens the ringing machine start'circuit; and, at contacts 243 removes the ring back tone from the calling line. v

R210, operating, reverses battery connections to the calling line at contacts 211, 212, 213 and 214 for metering purposes.

Restoration of the switches Upon termination lof the call, back bridge relay R210 will restore in response to the called partyv hanging up and line relay R220 will restore in response to the calling partyghanging up. R230 restores kin responsel to the restoration of R220, followed by the restoration of R240 and R250. As soon as R210, R220, R230 and R250 are restored, relay R310` operates over a circuit includingucontacts 222, 233, 2,15 and259, conductor 319 and contacts 345. R310` closes contacts 312 to busy mark. the connector until the connector and auxiliary switch wipers return to their normal position.

When R250restores contacts 298, itrcompletes a selfinterrupting circuit from a common release ground over contacts AV235 and 29S, conductor 316, contacts 395 and 351 ,andA motor `magnet M350 for operating M350 to step theconnector wipers to normal at which time said circuit is opened at ofi-normal. contacts 395. A circuit including oit-normal contacts 396 and 346 and self-interrupting contacts 341 is then completed for operating M340 to step the auxiliary switch ,wipers to normal at which time R310 will restore.

When ground is removed from the private conductor 200, the` switching relay R110 .will restore to complete a self-interrupting release circuit, including contacts 118, 122,133 and 109 for operating. M185. The selector wiperswill be advanced until they are at normal, that is when. .wipers 162, 1,63 and 16/tare on the last bank contacts as shown. .Oli-normal contacts 109 will then open to prevent furtheroperation of M185; and oit-normal contacts 108 will close to switch the release circuit to oi-normalfcontacts 106.and M190 to operate M190 until the auxiliaryswitch wipers return to normal at which time olf-normal `contacts open to prevent further opera* tion of,v M190. During said restoration, battery from M190willy not befound on conductor 134 since oil-normal contacts 107 are open; and, therefore, selector 102 may not be seized by another finder until it is fully restored.

While there has been described what is at present considered tobe the preferredembodiment ot the invention,

various modifications may be made therein; and it is conte-mplated to cover in the appended claims all such modications as fall within the true spirit and scope of the invention.4

What is claimed is;

l. In a single motion numerical switch having incoming conductors over which impulses are received and in* cluding a control wiper "and groups of 'bank contacts accessible to said wiper, magnet means for moving said wiper, marking relays associated with each of said groups, means operated independent of the position of said conltrol wiper inresponse to certain predetermined impulses in a digitalseries of impulses received over said conductors for operating said relays, circuits including contacts on each of said relays for marking the group of contacts associated therewith when each of said relays is operated, circuit means operated and eliective when said control wiper is standing upon a marked group of contacts .for operating said magnet means to move said wiper to the next group of contacts while said impulses 2. A,cornbinationI as claimedin claim 1 wherein said switch includes sets of line wipers and groups of contacts accessible toeach, and wherein said second means includes an auxiliary switch having wipers, together with means in said auxiliary switch operated responsive to said series of impulses for makng connections by way of its wipers to predetermined wiper sets.

3. In a telephone system having a line over which impulses are received, a numerical switch associated with said line and including a group control wiper and groups of bank contacts accessible thereto, magnet means in the Yswitch for moving said wiper, means for operating said magnet means to advance the wiper to said groups of bank contacts, markingmeans associated with each or'y said groups and operated in response to predetermined impulses in a series of impulses received over said line for marking said groups of contacts, said magnet means operated and effective in response to said wiper encountering a group of marked contacts for advancing said wiper to the next succeeding group, and means operated and eiective only when said wiper encounters the last contact in a group of contacts for again operating the marking means associated therewith to remove the marking from the group with which said last contact is associated.

s 4. In a single motion `numerical switch having a plurality of groups of outlets, line wipers and a control wiper having access to said outlets, an auxiliary switch having incoming conductors over which impulses are received, an intermediate relay having contacts, means in said auxiliary switch operated responsive to predetermined impulses in a series of impulses received over said incoming conductors for operating said intermediate relay, a pair of marking relays, means, including contacts on said intermediate relay, ior-operating said marking relays responsive to impulses following said predetermined impulses, magnet means in said numerical switch for advancing its wipers, circuit means including contacts on each of said marking relays, said control wiper and contacts accessible thereto for operating said magnet means when said relays are operated and while said impulses are being received to advance the wipers to succeeding groups of outlets, and circuit means including contacts associated with the last accessible outlets in said groups for restoring said relays.

5. In a telephone system as claimed in claim 4, wipers in said auxiliary switch, and means in said auxiliary switch operated responsive to said series of impulses for making connections to predetermined numerical switch wipers by way of said auxiliary switch wipers.

6. In a telephone system having means for extending a calling line to the wipers of a numerical switch by way of a inder and an auxiliary switch, a preparatory relay in said auxiliary switch, means operated responsive to a predetermined impulse in a series of impulses received by said auxiliary switch over said calling line for operating said relay, a rst marking relay, circuit means including contacts, on said preparatory relay for operating said marking relay responsive to the next succeeding impulse in said series of impulses, magnet means in said numerical switch operated responsive to the operation of said marking relay for advancing said numerical switch wipers a predetermined number of steps, means operated responsive to said wipers advancing the last of said predetermined number of steps for restoring said marking relay, means operated responsive to the restoration of said marking relay for advancing the wipers a predetermined number of steps, means operated responsive to a predetermined subsequent impulse in said series of impulses for again operating said preparatory relay, a second marking relay, circuit means including other contacts on saidpreparatory relay for operating said second marking relay responsive-to the next succeeding impulse in said series of impulses, Asaid magnet means operated and etective upon said wipers being advanced said lastmentioned .predeterminedl number of steps and said sec- @moet ond marking lrelay being operated for again advancing the wipers a predetermined number of steps.

7. In a combination as claimed in claim 6, means operated responsive to said wiper advancing to the last of said third-mentioned predetermined number of steps for restoring said second marking relay, means operated responsive to the restoration of said second marking relay for advancing the wipers a predetermined number of steps, means operated responsive to a predetermined subsequent impulse in said series of impulses for again operating said preparatory relay, and circuit means including said firstmentioned contacts on said preparatory relay for again operating said rst marking relay responsive to the next succeeding impulse in said series of impulses, said magnet means operated and effective upon said wipers being advanced said last-mentioned predetermined number of steps and said rst marking relay being operated for again advancing the wipers a predetermined number of steps.

8. In a telephone system having a line over which impulses are received, a single motion numerical switch having wipers and including groups of bank contacts accessible to said wipers, an auxiliary switch individual to said numerical switch and including wipers and bank contacts accessible to its wipers, some of said last-mentioned bank contacts terminating in wipers of said numerical switch, means for connecting said line to said auxiliary switch, magnet means in said numerical switch for moving its wipers, means associated with both of saiid switches for operating said magnet means to advance the numerical switch wipers to a predetermined group of bank contacts, means including said auxiliary switch wipers for simultaneously selecting the predetermined numerical switch wipers having access to said predetermined group, means in said auxiliary switch whereby said third and fourth means are operated responsive to and concurrent with a digital series of impulses received over said line, means for thereafter selectively operating said magnet means to move the numerical switch wipers to a predetermined contact in said predetermined group, and means for connecting said line to said predetermined contacts by way of said auxiliary switch wipers and said predetermined numerical switch wipers.

9. In a telephone system, a numerical switch having a plurality of sets of wipers and banks of contacts and having a common control wiper and groups of contacts accessible thereto, groups of outlets connected to each contact bank, magnet means for advancing said wipers over their respective contacts, an auxiliary switch associated with said numerical switch and having wipers and contacts accessible thereto, means for extending connections to a desired one of said numerical switch wiper sets by way of said auxiliary switch wipers and contacts, means whereby said last means is controlled by a digital series of impulses received by said auxiliary switch, means for operating the magnet means to advance the wipers to said groups of contacts, means for marking said common control contact groups in response to predetermined impulses in said series of received impulses, circuits completed when said common control wiper is standing upon a marked group of contacts for operating said magnet means to advance the wipers past said group and means for maintaining said marking on each group until the common control wiper passes said group, said magnet means advancing the numerical switch wiper sets over unwanted groups to a desired group accessible to said desired wiper set, in response to and concurrent with said received series of impulses.

l0. In a telephone system, a rotary switch having sets of connecting wipers, a common control wiper and groups of contacts accessible to each, an auxiliary switch associated with said rotary switch and having wipers and contact sets accessible thereto, means for operating said auxiliary switch, means whereby said last means is operated responsive to and concurrent with impulses of a received engage'iditferent contact sets accessible thereto, magnet' Y said magnet means upon said common control wiper series of impulses to move the auxiliary switch wipers to encountering said marking on said first contact group to move the rotary switch wipers past said marked contact group to the next group, means whereby said marking means is eective until the rotary switch wipers pass said marked contact group, circuits completed by said auxiliary switch wipers when moved to a certain contact set preceding said predetermined set in response to one digital series of received impulses to extend connections to a particular one of said connecting wiper sets of the rotary switch, circuits completed by said auxiliary switch wipers when moved to a certain contact set following said predetermined set of contacts in response to another digital series of received impulses to extend connections to the same wiper set of the rotary switch, one group of contacts accessible to said same wiper set being selected in response to said one digital series of impulses and another group of contacts accessible to said same wiper set being selected in response to said other digital series of impulses, and means whereby said magnet means is thereafter operated to advance the wipers of the rotary switch to select a set of contacts in the selected group of contacts.

` l1. In a telephone system, a single motion numerical switch having incoming conductors over which impulses are received and including a control wiper and groups of bank contacts accessible to said wiper, magnet means in said switch for moving said wiper, means for operating the magnet means to advance the wiper to said groups of bank contacts, marking relays associated with each of said groups, means operated independent of the position of said control wiper in response to certain predetermined impulses in a digital series of impulses received over said conductors for operating said relays, circuits including contacts on each of said relays for marking the group of contacts associated therewith when each of said relays is operated, circuit means effective when said control wiper is standing upon a marked group of contacts for operating said magnet means to move said wiper to the next group of contacts while said impulses are being received and circuit means eifective only when said wiper encounters the last contact in each group of contacts for restoring the relay and relay contacts associated therewith to remove the marking from the associated group of contacts.

12. The combination claimed in claim 11 wherein said switch includes sets of line wipers and groups of contacts accessible to each, and wherein said third-mentioned means includes an auxiliary switch having wipers, together with means in said auxiliary switch operated responsive to said series of impulses for making connections by way of its wipers to predetermined wiper sets.

13. In a telephone system, a single motion numerical switch having a plurality of groups of outlets, line wipers and a control wiper having access to said outlets, an auxiliary switch associated with said numerical switch and having incoming conductors over which impulses are received, an intermediate relay having contacts, means in said auxiliary switch operated responsive to predetermined impulses in a series of impulses received over said incoming conductors for operating said intermediate relay, a pair of marking relays, means including contacts on said intermediate relay for operating said marking relays responsive to impulses following said predetermined impulses, magnet means in said numerical switch for advancing its wipers, means for operating said magnet means to advance the wipers to said groups of bank i1,1 contacts, circuit means including contacts on each of said marking relays, said control wiper and contacts accessible thereto for operating said magnet means when said relays are operated and while said impulses are being received to advance the wipers to succeeding groups of outlets and circuit means including contacts associated with the last accessible outlets in said groups for restoring said relays.

14. ln a telephone system as claimed in claim 13, wipers in said auxiliary switch, and means in said auxiliary switch operated responsive to said series of impulses for making connections to predetermined numerical switch wipers by way of said auxiliary switch Wipers.

15. In a telephone system having a line over which impulses are received, a single motion numerical switch having wipers and including groups of bank contacts accessible to said wipers, an auxiliary switch individual to said numerical switch and including wipers and bank contacts accessible to its wipers, some of said last-mentioned bank contacts terminating in wipers of said numerical switch, means for connecting said line to said auxiliary switch, magnet means in said numerical switch for moving its wipers, means including marking relays, one of the wipers of said numerical switch and bank contacts accessible thereto for operating said magnet means to advance the numerical switch wipers to a predetermined group of bank contacts; means including said auxiliary switch wipers for selecting the predetermined numerical switch wipers having access to said predetermined group of bank contacts; means in said auxiliary switch whereby said third and fourth means are simultaneously operated responsive to and concurrent with a digital series of impulses received over said line; means for thereafter operating said magnet means to move the numerical switch Wipers to a predetermined contact in said predetermined group; and means for connecting said line to said predetermined contacts by Way of said auxiliary switch Wipers and said predetermined numerical switch wipers.

16. For use in a switching system, a single motion numerical switch having a plurality of sets of wipers and groups of outlets accessible to each set of wipers, magnet means for moving the wipers, an auxiliary switch associated with the numerical switch and having wipers and having incoming conductors over which impulses are received, marking relays for each of said groups of contacts, means controlled by said auxiliary switch and said marking relays in response to and concurrent With the receipt of a digital series of impulses over said conductors for operating said magnet means to move the wipers to a desired one of said groups of outlets, means thereafter controlled for causing the magnet means to move the wipers to a desired outlet in said desired one group of outlets, and means including the wipers of said auxiliary switch for connecting said incoming conductors to the numerical switch wiper set having access to said one group of outlets.

References Cited in the tile of this patent UNITED vSTATES PATENTS 2,529,471 Long Nov. 7, 1950 `2,548,673 Long Apr. 10, 1951 2,582,967 De Raedt Jan. 22, 1952 

